feat(aws-rds): add support for parameter groups

Now supports (Cluster) Parameter Groups. This is required to support
Aurora 5.7 engines (in particular, PostgreSQL with Aurora).

Fixes #719.

packages/@aws-cdk/aws-rds/lib/cluster-parameter-group-ref.ts

@@ -0,0 +1,60 @@
+import cdk = require('@aws-cdk/cdk');
+import { DBClusterParameterGroupName } from './rds.generated';
+
+/**
+ * A cluster parameter group
+ */
+export abstract class ClusterParameterGroupRef extends cdk.Construct {
+    /**
+     * Import a parameter group
+     */
+    public static import(parent: cdk.Construct, id: string, props: ClusterParameterGroupRefProps): ClusterParameterGroupRef {
+        return new ImportedClusterParameterGroup(parent, id, props);
+    }
+
+    /**
+     * Name of this parameter group
+     */
+    public abstract readonly parameterGroupName: DBClusterParameterGroupName;
+
+    /**
+     * Export this parameter group
+     */
+    public export(): ClusterParameterGroupRefProps {
+        return {
+            parameterGroupName: new DBClusterParameterGroupName(
+                    new cdk.Output(this, 'ParameterGroupName', { value: this.parameterGroupName }).makeImportValue())
+        };
+    }
+
+    /**
+     * Set a parameter on this parameter group
+     */
+    public abstract setParameter(key: string, value: string | undefined): void;
+}
+
+/**
+ * Properties to reference a cluster parameter group
+ */
+export interface ClusterParameterGroupRefProps {
+    parameterGroupName: DBClusterParameterGroupName;
+}
+
+/**
+ * An imported cluster parameter group
+ */
+class ImportedClusterParameterGroup extends ClusterParameterGroupRef {
+    public readonly parameterGroupName: DBClusterParameterGroupName;
+
+    constructor(parent: cdk.Construct, id: string, props: ClusterParameterGroupRefProps) {
+        super(parent, id);
+        this.parameterGroupName = props.parameterGroupName;
+    }
+
+    /**
+     * Set a parameter on this parameter group
+     */
+    public setParameter(_key: string, _value: string | undefined) {
+        // FIXME: Add annotation that we're dropping this on the floor
+    }
+}

packages/@aws-cdk/aws-rds/lib/cluster-parameter-group.ts

@@ -0,0 +1,70 @@
+import cdk = require('@aws-cdk/cdk');
+import { ClusterParameterGroupRef } from './cluster-parameter-group-ref';
+import { Parameters } from './props';
+import { cloudformation, DBClusterParameterGroupName } from './rds.generated';
+
+/**
+ * Properties for a cluster parameter group
+ */
+export interface ClusterParameterGroupProps {
+    /**
+     * Database family of this parameter group
+     */
+    family: string;
+
+    /**
+     * Description for this parameter group
+     */
+    description: string;
+
+    /**
+     * The parameters in this parameter group
+     */
+    parameters?: Parameters;
+}
+
+/**
+ * Defina a cluster parameter group
+ */
+export class ClusterParameterGroup extends ClusterParameterGroupRef {
+    public readonly parameterGroupName: DBClusterParameterGroupName;
+    private readonly parameters: Parameters = {};
+
+    constructor(parent: cdk.Construct, id: string, props: ClusterParameterGroupProps) {
+        super(parent, id);
+
+        const resource = new cloudformation.DBClusterParameterGroupResource(this, 'Resource', {
+            description: props.description,
+            family: props.family,
+            parameters: new cdk.Token(() => this.parameters),
+        });
+
+        for (const [key, value] of Object.entries(props.parameters || {})) {
+            this.setParameter(key, value);
+        }
+
+        this.parameterGroupName = resource.ref;
+    }
+
+    /**
+     * Set a single parameter in this parameter group
+     */
+    public setParameter(key: string, value: string | undefined) {
+        if (value === undefined && key in this.parameters) {
+            delete this.parameters[key];
+        }
+        if (value !== undefined) {
+            this.parameters[key] = value;
+        }
+    }
+
+    /**
+     * Validate this construct
+     */
+    public validate(): string[] {
+        if (Object.keys(this.parameters).length === 0) {
+            return ['At least one parameter required, call setParameter().'];
+        }
+        return [];
+    }
+}

packages/@aws-cdk/aws-rds/lib/cluster.ts

@@ -1,8 +1,9 @@
 import ec2 = require('@aws-cdk/aws-ec2');
 import kms = require('@aws-cdk/aws-kms');
 import cdk = require('@aws-cdk/cdk');
+import { ClusterParameterGroupRef } from './cluster-parameter-group-ref';
 import { DatabaseClusterRef, Endpoint } from './cluster-ref';
-import { BackupProps, DatabaseClusterEngine, InstanceProps, Login, Parameters } from './props';
+import { BackupProps, DatabaseClusterEngine, InstanceProps, Login } from './props';
 import { cloudformation, DBClusterEndpointAddress, DBClusterEndpointPort, DBClusterName, DBInstanceId } from './rds.generated';
 
 /**
@@ -84,8 +85,10 @@ export interface DatabaseClusterProps {
 
     /**
      * Additional parameters to pass to the database engine
+     *
+     * @default No parameter group
      */
-    parameters?: Parameters;
+    parameterGroup?: ClusterParameterGroupRef;
 }
 
 /**
@@ -155,6 +158,7 @@ export class DatabaseCluster extends DatabaseClusterRef {
             dbSubnetGroupName: subnetGroup.ref,
             vpcSecurityGroupIds: [this.securityGroupId],
             port: props.port,
+            dbClusterParameterGroupName: props.parameterGroup && props.parameterGroup.parameterGroupName,
             // Admin
             masterUsername: props.masterUser.username,
             masterUserPassword: props.masterUser.password,

packages/@aws-cdk/aws-rds/lib/index.ts

@@ -2,6 +2,8 @@ export * from './cluster';
 export * from './cluster-ref';
 export * from './instance';
 export * from './props';
+export * from './cluster-parameter-group';
+export * from './cluster-parameter-group-ref';
 
 // AWS::RDS CloudFormation Resources:
 export * from './rds.generated';

packages/@aws-cdk/aws-rds/test/integ.cluster.expected.json

@@ -305,6 +305,16 @@
         }
       }
     },
+    "ParamsA8366201": {
+      "Type": "AWS::RDS::DBClusterParameterGroup",
+      "Properties": {
+        "Description": "A nice parameter group",
+        "Family": "aurora5.6",
+        "Parameters": {
+          "character_set_database": "utf8mb4"
+        }
+      }
+    },
     "DatabaseSubnets56F17B9A": {
       "Type": "AWS::RDS::DBSubnetGroup",
       "Properties": {
@@ -360,6 +370,9 @@
       "Type": "AWS::RDS::DBCluster",
       "Properties": {
         "Engine": "aurora",
+        "DBClusterParameterGroupName": {
+          "Ref": "ParamsA8366201"
+        },
         "DBSubnetGroupName": {
           "Ref": "DatabaseSubnets56F17B9A"
         },

packages/@aws-cdk/aws-rds/test/integ.cluster.ts

@@ -1,12 +1,19 @@
 import ec2 = require('@aws-cdk/aws-ec2');
 import cdk = require('@aws-cdk/cdk');
 import { DatabaseCluster, DatabaseClusterEngine, Password, Username } from '../lib';
+import { ClusterParameterGroup } from '../lib/cluster-parameter-group';
 
 const app = new cdk.App(process.argv);
 const stack = new cdk.Stack(app, 'aws-cdk-rds-integ');
 
 const vpc = new ec2.VpcNetwork(stack, 'VPC', { maxAZs: 2 });
 
+const params = new ClusterParameterGroup(stack, 'Params', {
+    family: 'aurora5.6',
+    description: 'A nice parameter group',
+});
+params.setParameter('character_set_database', 'utf8mb4');
+
 const cluster = new DatabaseCluster(stack, 'Database', {
     engine: DatabaseClusterEngine.Aurora,
     masterUser: {
@@ -17,7 +24,8 @@ const cluster = new DatabaseCluster(stack, 'Database', {
         instanceType: new ec2.InstanceTypePair(ec2.InstanceClass.Burstable2, ec2.InstanceSize.Small),
         vpcPlacement: { subnetsToUse: ec2.SubnetType.Public },
         vpc
-    }
+    },
+    parameterGroup: params,
 });
 
 cluster.connections.allowDefaultPortFromAnyIpv4('Open to the world');

packages/@aws-cdk/aws-rds/test/test.cluster.ts

@@ -2,7 +2,7 @@ import { expect, haveResource } from '@aws-cdk/assert';
 import ec2 = require('@aws-cdk/aws-ec2');
 import cdk = require('@aws-cdk/cdk');
 import { Test } from 'nodeunit';
-import { DatabaseCluster, DatabaseClusterEngine, DatabaseClusterRef, Password, Username } from '../lib';
+import { ClusterParameterGroup, DatabaseCluster, DatabaseClusterEngine, DatabaseClusterRef, Password, Username } from '../lib';
 
 export = {
     'check that instantiation works'(test: Test) {
@@ -88,6 +88,40 @@ export = {
 
         test.done();
     },
+
+    'cluster with parameter group'(test: Test) {
+        // GIVEN
+        const stack = testStack();
+        const vpc = new ec2.VpcNetwork(stack, 'VPC');
+
+        // WHEN
+        const group = new ClusterParameterGroup(stack, 'Params', {
+            family: 'hello',
+            description: 'bye',
+            parameters: {
+                param: 'value'
+            }
+        });
+        new DatabaseCluster(stack, 'Database', {
+            engine: DatabaseClusterEngine.Aurora,
+            masterUser: {
+                username: new Username('admin'),
+                password: new Password('tooshort'),
+            },
+            instanceProps: {
+                instanceType: new ec2.InstanceTypePair(ec2.InstanceClass.Burstable2, ec2.InstanceSize.Small),
+                vpc
+            },
+            parameterGroup: group
+        });
+
+        // THEN
+        expect(stack).to(haveResource('AWS::RDS::DBCluster', {
+            DBClusterParameterGroupName: { Ref: 'ParamsA8366201' },
+        }));
+
+        test.done();
+    },
 };
 
 function testStack() {